Who is 'Insulate Britain'?

Insulate Britain is a group of activists who shot to prominence in August this year as an off-shoot from Extinction Rebellion.

They have caused chaos on stretches of the M25 in September, repeatedly blocking sections of the motorway by running in front of oncoming traffic.
They want the government to:

Fully fund and take responsibility for the insulation of all social housing in Britain by 2025
Produce - within four months - a legally binding national plan to pay for all homes in Britain to become low-energy and low-carbon by 2030 with a future aim of fully decarbonising society and the economy.

The government has previously announced plans to phase out the installation of new gas boilers by the mid-2030s, moving to low-carbon or ‘hydrogen-ready’ ones. It has also pledged £3.8 billion in new funding for the Social Housing Decarbonisation Fund, as part of a wider target to reach net-zero carbon emissions by 2050.